Image sensors including CMOS image sensor have a limited native dynamic range. A real scene may include dark portion and bright portion. If the sensor is adjusted to the dark portion, the captured image may include a dark portion that has recognizable details and a bright portion that is overexposed and thus is not recognizable. If the sensor is adjusted to the bright portion, the captured image may include a bright portion that has recognizable details and a dark portion that is underexposed and thus is not recognizable.
A high dynamic range (HDR) image may show both the dark portion having recognizable details and the bright portion having recognizable details. However, the current HDR techniques may not genuinely display the real scene that includes dark portion and bright portion in the real intensity scale. In HDR images, the intensity of dark portion is increased to include it in the lower end of the native dynamic range and the intensity of bright portion is decreased to include it in the higher end of the native dynamic range. Therefore, although both dark portion and bright portion have recognizable details, the dark portion and the bright portion may not be in real intensity scale.
Accordingly, methods and systems capable of capturing and displaying HDR images showing recognizable details in both dark portion and bright portion in a real intensity scale are demanded. The methods and systems capable of capturing and displaying HDR images of the present invention use the same image sensor and the same display having the same native dynamic ranges as that used in the current HDR techniques.
Corresponding reference characters indicate corresponding components throughout the several views of the drawings. Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention.